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* s390/idle: fix sequence handling vs cpu hotplugHeiko Carstens2012-07-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | The s390 idle accounting code uses a sequence counter which gets used when the per cpu idle statistics get updated and read. One assumption on read access is that only when the sequence counter is even and did not change while reading all values the result is valid. On cpu hotplug however the per cpu data structure gets initialized via a cpu hotplug notifier on CPU_ONLINE. CPU_ONLINE however is too late, since the onlined cpu is already running and might access the per cpu data. Worst case is that the data structure gets initialized while an idle thread is updating its idle statistics. This will result in an uneven sequence counter after an update. As a result user space tools like top, which access /proc/stat in order to get idle stats, will busy loop waiting for the sequence counter to become even again, which will never happen until the queried cpu will update its idle statistics again. And even then the sequence counter will only have an even value for a couple of cpu cycles. Fix this by moving the initialization of the per cpu idle statistics to cpu_init(). I prefer that solution in favor of changing the notifier to CPU_UP_PREPARE, which would be a different solution to the problem. Cc: stable@vger.kernel.org Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/smp: make absolute lowcore / cpu restart parameter accesses more robustHeiko Carstens2012-06-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | Setting the cpu restart parameters is done in three different fashions: - directly setting the four parameters individually - copying the four parameters with memcpy (using 4 * sizeof(long)) - copying the four parameters using a private structure In addition code in entry*.S relies on a certain order of the restart members of struct _lowcore. Make all of this more robust to future changes by adding a mem_absolute_assign(dest, val) define, which assigns val to dest using absolute addressing mode. Also the load multiple instructions in entry*.S have been split into separate load instruction so the order of the struct _lowcore members doesn't matter anymore. In addition move the prototypes of memcpy_real/absolute from uaccess.h to processor.h. These memcpy* variants are not related to uaccess at all. string.h doesn't seem to match as well, so lets use processor.h. Also replace the eight byte array in struct _lowcore which represents a misaliged u64 with a u64. The compiler will always create code that handles the misaligned u64 correctly. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/sigp: use sigp order code defines in assembly codeHeiko Carstens2012-06-05
| | | | | | | | | | Use sigp order code defines in assembly code as well. With this change all places that use sigp constants should have been converted to use self describing defines instead of directly using constants. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/smp: use sigp cpu status definitionsHeiko Carstens2012-06-05
| | | | | | | We got them from the kvm code, so let's use them. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/smp/kvm: unifiy sigp definitionsHeiko Carstens2012-06-05
| | | | | | | | | | The smp and the kvm code have different defines for the sigp order codes. Let's just have a single place where these are defined. Also move the sigp condition code and sigp cpu status bits to the new sigp.h header file. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/smp: remove redundant checkHeiko Carstens2012-06-05
| | | | | | | | | condition code "status stored" for sigp sense running always implies that only the "not running" status bit is set. Therefore no need to check if it is set. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/cpu: remove cpu "capabilities" sysfs attributeHeiko Carstens2012-05-30
| | | | | | | | | | | | | | | | | | | | It has been a big mistage to add the capabilities attribute to the cpus in sysfs: First the attribute only contains the cpu capability of primary cpus, which however is not necessarily (or better: unlikely) the type of cpu the kernel runs on, which is typically an IFL. In addition all information that is necessary is available in /proc/sysinfo already. So this attribute partially duplicated informations. So programs should look into the sysinfo file to retrieve all informations they are interested in. Since with this kernel release also the powersavings cpu attributes are removed this seems to be a good opportunity to remove another broken interface. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/kernel: Fix smp_call_ipl_cpu() for offline CPUsMichael Holzheu2012-05-30
| | | | | | | | | | | | | | | | If the IPL CPU is offline, currently the pcpu_delegate() function used by smp_call_ipl_cpu() does not work because pcpu_delegate() modifies the lowcore of the target CPU. In case of an offline IPL CPU currently the prefix register is zero but pcpu->lowcore still points to the old prefix page. Therefore the lowcore changes done by pcpu_delegate() have no effect. With this fix pcpu_delegate() now uses memcpy_absolute() and therefore also prepares the absolute zero lowcore if the target CPU has prefix register zero. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* s390/kernel: Remove OS info init function call and diag 308 for kdumpMichael Holzheu2012-05-23
| | | | | | | | | | | | | | | Because of a design change for stand-alone kdump the function that was done by the OS info init function is moved to the boot loader code. This has two implications that are implemented by this patch: a) The OS info init function is no longer called by the kernel b) The diag 308 subcode 1 reset is no longer done by the kdump boot code. This is necessary because otherwise the operation that is done now by the boot loader would be reversed. For the normal kexec based kdump mechansim the reset is already done by the kdump trigger code (e.g. panic or PSW restart). Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* Merge branch 'smp-hotplug-for-linus' of ↵Linus Torvalds2012-05-21
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull smp hotplug cleanups from Thomas Gleixner: "This series is merily a cleanup of code copied around in arch/* and not changing any of the real cpu hotplug horrors yet. I wish I'd had something more substantial for 3.5, but I underestimated the lurking horror..." Fix up trivial conflicts in arch/{arm,sparc,x86}/Kconfig and arch/sparc/include/asm/thread_info_32.h * 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (79 commits) um: Remove leftover declaration of alloc_task_struct_node() task_allocator: Use config switches instead of magic defines sparc: Use common threadinfo allocator score: Use common threadinfo allocator sh-use-common-threadinfo-allocator mn10300: Use common threadinfo allocator powerpc: Use common threadinfo allocator mips: Use common threadinfo allocator hexagon: Use common threadinfo allocator m32r: Use common threadinfo allocator frv: Use common threadinfo allocator cris: Use common threadinfo allocator x86: Use common threadinfo allocator c6x: Use common threadinfo allocator fork: Provide kmemcache based thread_info allocator tile: Use common threadinfo allocator fork: Provide weak arch_release_[task_struct|thread_info] functions fork: Move thread info gfp flags to header fork: Remove the weak insanity sh: Remove cpu_idle_wait() ...
| * s390: Use generic idle thread allocationThomas Gleixner2012-04-26
| | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Link: http://lkml.kernel.org/r/20120420124557.652574928@linutronix.de
| * smp: Add task_struct argument to __cpu_up()Thomas Gleixner2012-04-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Preparatory patch to make the idle thread allocation for secondary cpus generic. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Hirokazu Takata <takata@linux-m32r.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: David Howells <dhowells@redhat.com> Cc: James E.J. Bottomley <jejb@parisc-linux.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: David S. Miller <davem@davemloft.net> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Richard Weinberger <richard@nod.at> Cc: x86@kernel.org Link: http://lkml.kernel.org/r/20120420124556.964170564@linutronix.de
* | s390/smp: get rid of compile warningHeiko Carstens2012-05-16
|/ | | | | | | | | Add missing #ifdep CONFIG_HOTPLUG_CPU to get rid of this one: arch/s390/kernel/smp.c:229:13: warning: 'pcpu_free_lowcore' defined but not used [-Wunused-function] Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] Fix build errors (fallout from system.h disintegration)Heiko Carstens2012-03-30
| | | | | Signed-off-by: Heiko Carstens <h.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* Merge branch 'for-linus' of ↵Linus Torvalds2012-03-22
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 patches from Martin Schwidefsky: "The biggest patch is the rework of the smp code, something I wanted to do for some time. There are some patches for our various dump methods and one new thing: z/VM LGR detection. LGR stands for linux-guest- relocation and is the guest migration feature of z/VM. For debugging purposes we keep a log of the systems where a specific guest has lived." Fix up trivial conflict in arch/s390/kernel/smp.c due to the scheduler cleanup having removed some code next to removed s390 code. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: [S390] kernel: Pass correct stack for smp_call_ipl_cpu() [S390] Ensure that vmcore_info pointer is never accessed directly [S390] dasd: prevent validate server for offline devices [S390] Remove monolithic build option for zcrypt driver. [S390] stack dump: fix indentation in output [S390] kernel: Add OS info memory interface [S390] Use block_sigmask() [S390] kernel: Add z/VM LGR detection [S390] irq: external interrupt code passing [S390] irq: set __ARCH_IRQ_EXIT_IRQS_DISABLED [S390] zfcpdump: Implement async sdias event processing [S390] Use copy_to_absolute_zero() instead of "stura/sturg" [S390] rework idle code [S390] rework smp code [S390] rename lowcore field [S390] Fix gcc 4.6.0 compile warning
| * [S390] kernel: Pass correct stack for smp_call_ipl_cpu()Michael Holzheu2012-03-13
| | | | | | | | | | | | | | | | | | | | | | Currently pcpu_devices->panic_stack is passed to pcpu_delegate() in smp_call_ipl_cpu(). This is wrong because pcpu_delegate() expects the bottom (high address) of the stack and pcpu_devices->panic_stack points to the top (low address). We now pass the bottom of the stack which is pcpu_devices->panic_stack + PAGE_SIZE. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * [S390] kernel: Add OS info memory interfaceMichael Holzheu2012-03-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to allow kdump based stand-alone dump, some information has to be passed from the old kernel to the new dump kernel. This is done via a the struct "os_info" that contains the following fields: * crashkernel base and size * reipl block * vmcoreinfo * init function A pointer to os_info is stored at a well known storage location and the whole structure as well as all fields are secured with checksums. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * [S390] kernel: Add z/VM LGR detectionMichael Holzheu2012-03-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently the following mechanisms are available to move active Linux on System z instances between machines: * z/VM 6.2 SSI (Single System Image) * Suspend/resume For moving Linux instances in this patch the term LGR (Linux Guest Relocation) is used. Because such an operation is critical, it should be detectable from Linux. With this patch for both, a live system and a kernel dump, the information about LGRs is accessible. To identify a guest, stsi and stfle data is used. A new function lgr_info_log() compares the current data (lgr_info_cur) with the last recorded one (lgr_info_last). In case the two data sets differ, lgr_info_cur is logged to the "lgr" s390dbf. The following trigger points call lgr_info_log(): * panic * die * kdump * LGR timer * PSW restart * QDIO recovery * resume This patch also changes the s390dbf hex_ascii view. Now only printable ASCII characters are shown. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * [S390] irq: external interrupt code passingHeiko Carstens2012-03-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The external interrupt handlers have a parameter called ext_int_code. Besides the name this paramter does not only contain the ext_int_code but in addition also the "cpu address" (POP) which caused the external interrupt. To make the code a bit more obvious pass a struct instead so the called function can easily distinguish between external interrupt code and cpu address. The cpu address field however is named "subcode" since some external interrupt sources do not pass a cpu address but a different parameter (or none at all). Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * [S390] rework idle codeMartin Schwidefsky2012-03-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Whenever the cpu loads an enabled wait PSW it will appear as idle to the underlying host system. The code in default_idle calls vtime_stop_cpu which does the necessary voodoo to get the cpu time accounting right. The udelay code just loads an enabled wait PSW. To correct this rework the vtime_stop_cpu/vtime_start_cpu logic and move the difficult parts to entry[64].S, vtime_stop_cpu can now be called from anywhere and vtime_start_cpu is gone. The correction of the cpu time during wakeup from an enabled wait PSW is done with a critical section in entry[64].S. As vtime_start_cpu is gone, s390_idle_check can be removed as well. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * [S390] rework smp codeMartin Schwidefsky2012-03-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Define struct pcpu and merge some of the NR_CPUS arrays into it, including __cpu_logical_map, current_set and smp_cpu_state. Split smp related functions to those operating on physical cpus and the functions operating on a logical cpu number. Make the functions for physical cpus use a pointer to a struct pcpu. This hides the knowledge about cpu addresses in smp.c, entry[64].S and swsusp_asm64.S, thus remove the sigp.h header. The PSW restart mechanism is used to start secondary cpus, calling a function on an online cpu, calling a function on the ipl cpu, and for the nmi signal. Replace the different assembler functions with a single function restart_int_handler. The new entry point calls a function whose pointer is stored in the lowcore of the target cpu and it can wait for the source cpu to stop. This covers all existing use cases. Overall the code is now simpler and there are ~380 lines less code. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* | sched: Cleanup cpu_active madnessPeter Zijlstra2012-03-12
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Stepan found: CPU0 CPUn _cpu_up() __cpu_up() boostrap() notify_cpu_starting() set_cpu_online() while (!cpu_active()) cpu_relax() <PREEMPT-out> smp_call_function(.wait=1) /* we find cpu_online() is true */ arch_send_call_function_ipi_mask() /* wait-forever-more */ <PREEMPT-in> local_irq_enable() cpu_notify(CPU_ONLINE) sched_cpu_active() set_cpu_active() Now the purpose of cpu_active is mostly with bringing down a cpu, where we mark it !active to avoid the load-balancer from moving tasks to it while we tear down the cpu. This is required because we only update the sched_domain tree after we brought the cpu-down. And this is needed so that some tasks can still run while we bring it down, we just don't want new tasks to appear. On cpu-up however the sched_domain tree doesn't yet include the new cpu, so its invisible to the load-balancer, regardless of the active state. So instead of setting the active state after we boot the new cpu (and consequently having to wait for it before enabling interrupts) set the cpu active before we set it online and avoid the whole mess. Reported-by: Stepan Moskovchenko <stepanm@codeaurora.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1323965362.18942.71.camel@twins Signed-off-by: Ingo Molnar <mingo@elte.hu>
* Merge branch 'for-linus' of ↵Linus Torvalds2012-01-09
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (31 commits) [S390] disassembler: mark exception causing instructions [S390] Enable exception traces by default [S390] return address of compat signals [S390] sysctl: get rid of dead declaration [S390] dasd: fix fixpoint divide exception in define_extent [S390] dasd: add sanity check to detect path connection error [S390] qdio: fix kernel panic for zfcp 31-bit [S390] Add s390x description to Documentation/kdump/kdump.txt [S390] Add VMCOREINFO_SYMBOL(high_memory) to vmcoreinfo [S390] dasd: fix expiration handling for recovery requests [S390] outstanding interrupts vs. smp_send_stop [S390] ipc: call generic sys_ipc demultiplexer [S390] zcrypt: Fix error return codes. [S390] zcrypt: Rework length parameter checking. [S390] cleanup trap handling [S390] Remove Kerntypes leftovers [S390] topology: increase poll frequency if change is anticipated [S390] entry[64].S improvements [S390] make arch/s390 subdirectories depend on config option [S390] kvm: move cmf host id constant out of lowcore ... Fix up conflicts in arch/s390/kernel/{smp.c,topology.c} due to the sysdev removal clashing with "topology: get rid of ifdefs" which moved some of that code around.
| * [S390] outstanding interrupts vs. smp_send_stopMartin Schwidefsky2011-12-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The panic function will first print the panic message to the console, then stop additional cpus with smp_send_stop and finally call the function on the panic notifier list. In case of an I/O based console the panic message will cause I/O to be started and a function on the panic notifier list will wait for the completion of the I/O. That does not work if an I/O completion interrupt has already been delivered to a cpu that is then stopped by smp_send_stop. To break this cyclic dependency add code to smp_send_stop that gives the additional cpu the opportunity to complete outstanding interrupts. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * [S390] topology: increase poll frequency if change is anticipatedHeiko Carstens2011-12-27
| | | | | | | | | | | | | | | | | | | | | | Increase cpu topology change poll frequency if a change is anticipated. Otherwise a user might be a bit confused to have to wait up to a minute in order to see a change this should be visible immediatly. However there is no guarantee that the change will happen during the time frame the poll frequency is increased. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * [S390] entry[64].S improvementsMartin Schwidefsky2011-12-27
| | | | | | | | | | | | | | | | | | Another round of cleanup for entry[64].S, in particular the program check handler looks more reasonable now. The code size for the 31 bit kernel has been reduced by 616 byte and by 528 byte for the 64 bit version. Even better the code is a bit faster as well. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * [S390] topology: get rid of ifdefsHeiko Carstens2011-12-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove all ifdefs from topology code and also only compile it for the CONFIG_SCHED_BOOK case. The new code selects SCHED_MC if SCHED_BOOK is selected. SCHED_MC without SCHED_BOOK is not possible anymore. Furthermore various sysfs attributes are not available anymore for the !SCHED_BOOK case. In particular all attributes that correspond to CPU polarization. But since all real world kernels have SCHED_BOOK selected anyway this doesn't matter too much. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * [S390] kernel: Fix smp_switch_to_ipl_cpu() stack frame setupMichael Holzheu2011-12-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, when smp_switch_to_ipl_cpu() is done, the backchain in the dump analysis tool crash looks like the following: #0 [1f746e70] __machine_kexec at 11dd92 #1 [1f746eb8] smp_restart_cpu at 11820e #0 [00907eb0] cpu_idle at 10602e #1 [00907ef8] start_kernel at 979a08 It would be good to see the registers of the interrupted function. To achieve this, the backchain on the new stack has to be set to zero. This looks then like the following: #0 [1f746e70] __machine_kexec at 11dd8e #1 [1f746eb8] smp_restart_cpu at 11820a PSW: 0706000180000000 00000000005c6fe6 (vtime_stop_cpu+134) GPRS: 0000000000000000 00000000005c6fe6 0000000001ad0228 0000000001ad0248 0000000000907f08 0000000001ad0b40 0000000000979344 0000000000000000 00000000009c0000 00000000009c0010 00000000009ab024 0000000001ad0200 0000000001ad0238 00000000005cc9d8 000000000010602e 0000000000907e68 #0 [00907eb0] cpu_idle at 10602e #1 [00907ef8] start_kernel at 979a08 In addition to this, now also the correct PSW is stored in the pt_regs structure that is located at the start of the panic stack. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * [S390] irq: fix accounting of external call/emergency signalHeiko Carstens2011-12-27
| | | | | | | | | | | | | | | | | | Mask the extint_code parameter of the smp external interrupt handler to get the interruption code. Otherwise emergency call interrupts erroneously might be accounted as emergency signal interrupts. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* | cpu: convert 'cpu' and 'machinecheck' sysdev_class to a regular subsystemKay Sievers2011-12-21
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This moves the 'cpu sysdev_class' over to a regular 'cpu' subsystem and converts the devices to regular devices. The sysdev drivers are implemented as subsystem interfaces now. After all sysdev classes are ported to regular driver core entities, the sysdev implementation will be entirely removed from the kernel. Userspace relies on events and generic sysfs subsystem infrastructure from sysdev devices, which are made available with this conversion. Cc: Haavard Skinnemoen <hskinnemoen@gmail.com> Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Borislav Petkov <bp@amd64.org> Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk> Cc: Len Brown <lenb@kernel.org> Cc: Zhang Rui <rui.zhang@intel.com> Cc: Dave Jones <davej@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [S390] irqstats: split IPI interrupt accountingHeiko Carstens2011-10-30
| | | | | | | | | We use both the external call and emergency call IPIs to signal remote cpus. Therefore it makes sense to account them differently withing /proc/irqstats so we actually know what happened. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] smp: external call vs. emergency signalMartin Schwidefsky2011-10-30
| | | | | | | | Use a sigp sense running to decide which signal processor order to use for an ipi. If the target cpu is running use external call, if the target cpu is not running use emergency signal. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] cleanup psw related bits and piecesMartin Schwidefsky2011-10-30
| | | | | | | | | | Split out addressing mode bits from PSW_BASE_BITS, rename PSW_BASE_BITS to PSW_MASK_BASE, get rid of psw_user32_bits, remove unused function enabled_wait(), introduce PSW_MASK_USER, and drop PSW_MASK_MERGE macros. Change psw_kernel_bits / psw_user_bits to contain only the bits that are always set in the respective mode. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] kdump backend codeMichael Holzheu2011-10-30
| | | | | | | | This patch provides the architecture specific part of the s390 kdump support. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] Force PSW restart on online CPUMichael Holzheu2011-10-30
| | | | | | | | | | | | | PSW restart can be triggered on offline CPUs. If this happens, currently the PSW restart code fails, because functions like smp_processor_id() do not work on offline CPUs. This patch fixes this as follows: If PSW restart is triggered on an offline CPU, the PSW restart (sigp restart) is done a second time on another CPU that is online and the old CPU is stopped afterwards. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] smp: remove pointless comments in startup_secondary()Heiko Carstens2011-08-03
| | | | | | | | Remove pointless comments in startup_secondary(). There is not too much value in having comments like e.g. "call cpu notifiers" just before a call to notify_cpu*(). Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
* [S390] cpu hotplug: on cpu start wait until being marked activeHeiko Carstens2011-08-03
| | | | | | | | | | | | This is the same as fd8a7de1 "x86: cpu-hotplug: Prevent softirq wakeup on wrong CPU". Unlike on x86 this doesn't fix a bug on s390 since we do not have threaded interrupt handlers. However we want to keep the same initialization order like on x86. This should prevent bugs caused by code which assumes (and relies on) the init order is the same on each architecture. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
* [S390] Add PSW restart shutdown triggerMichael Holzheu2011-08-03
| | | | | | | | | | | | | With this patch a new S390 shutdown trigger "restart" is added. If under z/VM "systerm restart" is entered or under the HMC the "PSW restart" button is pressed, the PSW located at 0 (31 bit) or 0x1a0 (64 bit) bit is loaded. Now we execute do_restart() that processes the restart action that is defined under /sys/firmware/shutdown_actions/on_restart. Currently the following actions are possible: reipl (default), stop, vmcmd, dump, and dump_reipl. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
* [S390] disable cpu measurement alerts on a dying cpuJan Glauber2011-07-24
| | | | | | | | | | The cpu measurement alerts that are used for instance by oprofile for hardware sampling are not turned off on a cpu that is going offline. Add the appropriate control register bit that should be disabled to the list. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] allow setting of upper 32 bit in smp_ctl_set_bitJan Glauber2011-06-22
| | | | | | | | | | | The bit shift operation in smp_ctl_set_bit does not specify the type of the shifted bit so integer is used as default. Therefore it is not possible to set bits in the upper 32 bit of the control register if the kernel runs in 64 bit mode. Fix this by specifying the type as unsigned long. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] irq: merge irq.c and s390_ext.cHeiko Carstens2011-05-26
| | | | | | | | Merge irq.c and s390_ext.c into irq.c. That way all external interrupt related functions are together. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] cpu hotplug: fix external interrupt subclass mask handlingHeiko Carstens2011-05-23
| | | | | | | | | | | When disabling a cpu all external interrupt subclass masks in control register 0 get cleared. However instead of the service signal subclass mask bit an unused bit got cleared. Accidently (or luckily) the service subclass mask gets cleared with the pfault_fini() call that happens just before the rest of the subclass mask bits get cleared. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
* [S390] convert old cpumask API into new oneKOSAKI Motohiro2011-05-23
| | | | | | | Adapt new API. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] smp: add __noreturn attribute to cpu_die()Heiko Carstens2011-05-23
| | | | | | | | | Add missing __noreturn attribute to cpu_die(): arch/s390/kernel/smp.c:691:6: error: symbol 'cpu_die' redeclared with different type Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* sched: Provide scheduler_ipi() callback in response to smp_send_reschedule()Peter Zijlstra2011-04-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | For future rework of try_to_wake_up() we'd like to push part of that function onto the CPU the task is actually going to run on. In order to do so we need a generic callback from the existing scheduler IPI. This patch introduces such a generic callback: scheduler_ipi() and implements it as a NOP. BenH notes: PowerPC might use this IPI on offline CPUs under rare conditions! Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Acked-by: Chris Metcalf <cmetcalf@tilera.com> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Reviewed-by: Frank Rowand <frank.rowand@am.sony.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20110405152728.744338123@chello.nl
* [S390] smp: remove cpu hotplug messagesHeiko Carstens2011-01-05
| | | | | | | | | | Get rid of messages that indicate if a cpu went online or offline. There is nothing special about this anymore and these messages might flood the kernel log buffer which makes debugging harder since more important messages might be overwritten. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] smp/idle: call init_idle() before starting a new cpuHeiko Carstens2011-01-05
| | | | | | | | | | | Call init_idle() which (re-)initializes the idle task structure before it gets used on a new cpu. That way we can also get rid of the odd preempt_enable_no_resched() call we have in the cpu offline path within cpu_idle(). That call prevented preempt count imbalances between cpu hotplug operations. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] smp: delay idle task creationHeiko Carstens2011-01-05
| | | | | | | | | | | | Delay idle task creation until a cpu gets set online instead of creating them for all possible cpus at system startup. For one cpu system this should safe more than 1 MB. On my debug system with lots of debug stuff enabled this saves 2 MB. Same as on x86. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] irq: have detailed statistics for interrupt typesHeiko Carstens2011-01-05
| | | | | | | | | | | | | | | | | | | | | | Up to now /proc/interrupts only has statistics for external and i/o interrupts but doesn't split up them any further. This patch adds a line for every single interrupt source so that it is possible to easier tell what the machine is/was doing. Part of the output now looks like this; CPU0 CPU2 CPU4 EXT: 3898 4232 2305 I/O: 782 315 245 CLK: 1029 1964 727 [EXT] Clock Comparator IPI: 2868 2267 1577 [EXT] Signal Processor TMR: 0 0 0 [EXT] CPU Timer TAL: 0 0 0 [EXT] Timing Alert PFL: 0 0 0 [EXT] Pseudo Page Fault [...] NMI: 0 1 1 [NMI] Machine Checks Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* [S390] cleanup facility list handlingMartin Schwidefsky2010-10-25
| | | | | | | Store the facility list once at system startup with stfl/stfle and reuse the result for all facility tests. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>